[El Exorcisto]

I use Black beauty blasting grit in my 10 gallon and it's really great stuff. I swear it's the same stuff that's packaged as Tahitian Moon. Here is the chemical makeup according to the manufacturer:

Silicon Dioxide= 47.20%, Aluminum oxide= 21.39%, Titanium dioxide= 1.01%, Ferric Oxide= 19.23%, Calcium oxide= 6.80%, Magnesium Oxide= 1.47%, Potassium Oxide= 1.60% and Sodium Oxide= 0.62%

There's nothing there that scares me about it at all, and it holds plants great.